246 Gr. A. and W. G. MacCallum, 



worm that the anterior end at least can be telescoped to a sliglit degree.. 

 But in additiou one finds the hinder portion of the body elongated 

 in some specimens in a way that could hardly be explained on these 

 grounds and it is often in these cases that the great accumulation 

 of eggs in the Uterus is responsible for much increase in the bulk 

 of the body. They are white or greyish white and fairly trans- 

 lucent so that the larger organs can be seen througli the skin. 



The anterior end of the body, as shown in the Sketches, is 

 provided with five curiously recurved niuscular lobes which when 

 seen in face liave an arrangement somewhat like that of the petals 

 of a violet. The dorsal group is composed of two rather large 

 sharply recurved lobes separated by a sniall rounded one which is 

 much more erect. The ventral group is foimed of two still larger 

 lobes which are partly divided from one another by a deep median 

 indentation. They, too, curve back sharply. At the extremity 

 between these lobes there is a central depression, the mouth, which 

 leads directly into the thin walled prephai-ynx. There seems thus 

 to be no special sucker like arrangement about the mouth but the 

 lobes as well as the whole anterior extremity of the body are so 

 solidly built of muscle fibers that it seems probable that in some 

 way they coustitute a sucking or adhering apparatus, 



The ventral sucking disc is relatively large and seems extre- 

 mely powerful. In life it moves actively and may be made concave 

 in both directions although in the fixed specimen it tends to evert 

 itself into a convex structure. The body which is fused into it is 

 especially thick over this disc projecting behind it into a posterior 

 elongation of varying extent and anteriorly into the relatively 

 Short neck. The posterior end of the body is often transversely 

 indented and it is evident that the excretory apparatus opens in 

 this indentation. 



The large ventral sucking disc measures 1,7 X 0,7 mm and is 

 elliptical in form. It is divided transversely into about sixteen 

 grooves the ridges between which are quite sharp and provided with 

 little pyramids of muscle fibers which run in the long axis of the 

 worm, that is at right angles to the ridge. Below these there is 

 a triangulär space filled with cells on each side of which begins 

 the radial muscle which forms the sucker-like hollow of the groove. 

 On each side the groove terminates in a rounded complete sucker. 

 Anteriorly and posteriorly a pair of these suckers comes together 

 without an intervening muscular groove so that there are thirty-six 



